This application requests continued funding for our highly successful program of Research Training in the Dementias of Aging. This program, which began in 1987, teaches postdoctoral physicians and psychologists how to conduct high quality research on disorders of great public health significance among the elderly. Most of the research training is the context of currently-funded projects at the Johns Hopkins School of Medicine. These include clinical and population-based surveys, longitudinal follow-up studies, laboratory-based case-control studies and clinical trials in Alzheimer's disease, Huntington's disease, Down's syndrome, delirium, and other syndromes of cognitive impairment. Research settings include the community, general hospital, and the nursing home, in addition to the laboratory. A large number of projects in the clinical neurosciences are currently available to fellows, with particular emphases on: instrument and measurement development; correlations between clinical/functional indicators and brain abnormalities revealed by neuroimaging methods; and application of genetic knowledge and methodology to the problems of dementing illnesses. Fellows receive two years of research tutelage and supervised experience, a full didactic program, and experience in the neuropsychiatry clinics. Past graduates of this training program have gone on to successful hospital and medical-school-based careers as clinical investigators.